AND CONSEEVATOET. 



11 



the lowest are so far from the glass that they must be drawn 

 and blauched and miserable. 



Fig. 2. 



The question of material is one of comparatively small im- 

 portance, because bouses of equal value as regards plant pro- 

 duction may be secured in either iron or wood, and with either 

 brick or stone or concrete walls. But of necessity there may 

 arise occasions for particular care as to selection of materials, 

 and a few remarks on this part of the subject will be appro- 

 priate in this place. To begin witb : — at ground line, the ques- 

 tion arises, shall we have walls or glass only from head to foot ? 

 The Paxtonian houses consist of lights resting in a wooden 

 trougli which catches and carries away the rain water, and the 

 thrust of the rafters is received by " chairs" or rests of wood 

 which lodge on blocks of concrete or stone sunk in the ground. 

 Between walls of brick and wood the diflerence is all in favour 



